Remove background in opencv to make text clearer

Question

I am trying to create an application that can read text from an image. But I have problems clearing the background. I need results, for example:

Input Image 1:

Output Image 1:

This is the code I tried:

cvtColor(org, tmp, CV_BGR2GRAY); 
normalize(tmp, tmp, 0, 255, NORM_MINMAX); 
threshold(tmp, dst, 0, 255, CV_THRESH_OTSU);

Answer 1

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